`hockeystick` includes functions to download and visualized climate data. Data is optionally cached.

### Retrieve NOAA/ESRL Mauna Loa CO2 Observatory concentration data and plot:

    library(hockeystick)
    ml_co2 <- get_carbon()
    plot_carbon(ml_co2)

### Retrieve GCP global CO2 emissions and plot:

    emissions <- get_emissions()
    plot_emissions(emissions)

    plot_emissions_with_land(emissions)

### Visualize cumulative emissions by country:

    emissions_map()

### Retrieve NASA/GISS global surface temperature anomaly data and plot:

    anomaly <- get_temp()
    plot_temp(anomaly)

### Plot relationship between temperature anomaly and carbon:

    plot_carbontemp()

### Visualize warming using Ed Hawkins styled “warming stripes”:

    warming_stripes()

    warming_stripes(stripe_only = TRUE, col_strip = viridisLite::viridis(11))

### Retrieve tide gauge and satellite sea level data and plot:

    gmsl <- get_sealevel()
    plot_sealevel(gmsl)

### Retrieve July annual Arctic Sea Ice Index and plot:

    seaice <- get_seaice()
    plot_seaice(seaice)

`get_seaice()` arguments can be modified to download Antarctic sea ice, and allow any month.

You can also visualize sea ice by month and year:

    arcticice <- get_icecurves()
    plot_icecurves(arcticice)

### Retrieve NOAA HURDAT2 hurricane data and plot:

    hurricanes <- get_hurricanes()
    plot_hurricanes(hurricanes)

    plot_hurricane_nrg(hurricanes)

### Retrieve NOAA/ESRL CH4 Globally averaged mean data and plot:

    ch4 <- get_methane()
    plot_methane(ch4)

### Retrieve Vostok paleo ice core data and plot:

    vostok <- get_paleo()
    plot_paleo(vostok)

### Managing the cache

By default, no climate data is cached, and all data is downloaded every time any of the `get_` functions is called. To cache data for future use, use the `write_cache = TRUE` option, available in all of the `get_` functions. To download and cache all data use `hockeystick_update_all()`. To view the files, date, and size of cached data use `hockeystick_cache_details()`. To re-download data from the source use the `use_cache = FALSE` argument in any of the `get_` functions, for example: `get_carbon(use_cache = FALSE, write_cache = TRUE)`. To delete all cached data use `hockeystick_cache_delete_all()`.

Users may also cache data by default by adding `options(hs_write_cache = TRUE)`to their script or `.Rprofile` file.